填空题 A LAN can be configured in a ____, ____or ____topology.
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填空题 The protocol that supports electronic mail on the Internet is ____.
填空题 The ____is a standard identifier for specifying information on the Internet
填空题 A ____is needed to access a page on the WWW.
填空题 THe URL defines four things:____,____,____, and ____.
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